1. Field of the Invention
The present invention relates in general to feeding robots, and more particularly to a feeding robot which is capable of drawing a glass panel for a liquid crystal display from a cassette without bringing it into collision with the cassette, and then feeding the drawn glass panel with a reduced error, and a method for controlling the same.
2. Description of the Prior Art
Liquid crystal displays (LCDs) are each generally manufactured with a number of transistors integrated on a glass panel, which is a main substrate of the LCD. The LCD glass panel normally remains loaded in a cassette, and is then automatically fed from the cassette to the next process by a feeding robot as needed.
A description will hereinafter be given of a typical operation of feeding the above LCD glass panel.
FIGS. 1a and 1b are plan views illustrating the operation of a conventional feeding robot.
With reference to FIGS. 1a and 1b, provided that an LCD glass panel 3, which is an object to be fed, remains loaded in a cassette 4 under the condition that it is turned at a certain angle relative to its correct position, it will be misaligned with a hand 2 of a feeding robot 1 accessing to feed it.
Accordingly, when the hand 2 of the feeding robot 1 moves to draw the LCD glass panel 3 from the cassette, a portion 5 of the glass panel 3 may be brought into collision with the cassette 4 and then get broken. This may in turn result in a loss in components, a delay in working process, a degradation in productivity, etc.
Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a feeding robot which is capable of drawing a glass panel for a liquid crystal display from a cassette without bringing it into collision with the cassette, and then feeding the drawn glass panel with a reduced error, and a method for controlling the same.
In accordance with one aspect of the present invention, the above and other objects can be accomplished by the provision of a feeding robot having a body, a plurality of joints, a plurality of links, each for interconnecting corresponding ones of the joints, and a hand for holding an object to be fed, the robot comprising distance sensing means for measuring a distance between the hand and the object; traverse sensing means for sensing a movement of the feeding robot to a predetermined target position; and a controller for controlling the feeding robot on the basis of information sensed by the traverse sensing means and distance sensing means.
In accordance with another aspect of the present invention, there is provided a method for controlling a feeding robot, comprising the steps of a) determining whether an object to be fed has been accurately aligned with a traveling axis of the feeding robot; b) calculating a turned angle of the object relative to the traveling axis if the object has not been accurately aligned with the traveling axis; c) turning the robot by the turned angle and then drawing the object; d) moving the robot to a target position and calculating a correction value for the target position; and e) correcting the target position by the calculated correction value.